The objective is to arry out the second phase of a long-term randomized controlled trial on ability to lower blood pressure and prevent development of hypertension in hypertension-prone persons age 30-44. Two hundred hypertension-prone persons were identified among working people in Chicago companies to permit development of this trail on the basis of general populations of employed men and women. The key criterion for hypertension-proneness was a high normal diastolic pressure based on multiple readings on separate occasions, using the Hawksley random zero device. Eligible participants were randomly assigned to a Monitored (Control) or active Intervention Group, involving motivation and education to effect and sustain changes in life styles, particularly improved habits of nutrition, to correct overweight and high sodium intake, and regular frequent moderate rhythmic exercise to improve cardio-pulmonary fitness and to slow heart rate. The primary endpoint in the first phase of the trial was mean diastolic blood pressure, assessed objectively and with special efforts to minimize bias, at semi-annual examinations. If the special intervention efforts were successful in regard to effecting significant, sustained decreases in weight, sodium intake, heart rate, and blood pressure, after a majority of participants had completed at least two years of follow-up, then support was to be sought for the second phase of this study, with the addition of the incidence of high blood pressure and/or hypertension as a primary endpoint. Three years of additional support are being sought to implement Phase II of this prevention trial, in which the goal is to follow-up all randomized participants for a minimum of five years, in order to determine the efficacy of the special intervention program in preventing the development of high blood pressure and/or hypertension in hypertension-prone persons.